A conventional tear-open closure has a closure part fastened to the neck of a container and has a base supporting two tubular extraction nozzles. Each extraction nozzle contains a separate gasket with a puncture point which can be perforated by a needle. The top of each extraction nozzle is covered by a removable piece of foil. Such closure is disclosed in DE-OS No. 25 01 428.
Another conventional tear-open closure has a closure part fastened to one end of a blood pouch or bag which has a convex shape. Two tubular extraction nozzles are mounted on this closure part, with each nozzle covered by a separate cap with a scored portion. Each removable cap part has an actuation member extending from it. Such closure is disclosed in U.S. Pat. No. 3,509,879 to Bathish et al.
Conventional tear-open closures of this type are disadvantageous in that they are relatively complex and expensive to manufacture. Additionally, the conventional tear-open closures tend to be relatively large and require significant amounts of material.